1. Field of the Invention:
The invention relates to a process for the separation of sulfur from a sulfur/alkaline solution suspension, wherein the suspension is heated to a temperature above the melting temperature of sulfur and is conducted under pressure to a separating tank containing a separating chamber, alkaline solution chamber and sulfur chamber; from which tank there is continuously withdrawn, on the one hand, settled liquid sulfur and, on the other hand, alkaline solution; the invention further relates to apparatus and in particular to a separating tank suitable for performing the process.
2. Prior Art
German Pat. No. 2,904,845 discloses a process for the separation of a so-called Stretford alkaline solution from sulfur. In this conventional process, a steam blanket or cushion is maintained in each separating tank, above the suspension, in order to maintain the pressure under which the separating tank is held at the saturation pressure, while the alkaline solution scrubbing agent is removed via an overflow. The reference furthermore provides a separating tank for conducting the process, this tank comprising a separating chamber to which is connected, on the one hand, an alkaline solution chamber by way of an overflow weir and, on the other hand, a sulfur chamber by way of a continuous, immersed wall, the tank chambers being in communication with one another above the separating chamber, the alkaline solution chamber and the sulfur chamber, and being designed as a space for steam. A separating pressure control device is connected to this steam space. By saturation pressure is meant the vapor pressure of the suspension.
The aforedescribed process has the disadvantage that a specific steam blanket must be maintained at all times in order to keep the saturation pressure ambient in the separating chamber. As a consequence, there is a danger that effective separation of the sulfur/alkaline solution suspension is not ensured in case of unforeseen trouble during which a steam blanket is not provided.